1. Technical Field
The invention relates to a method for producing packs, in particular cigarette packs, from blanks, wherein individual regions, in particular folding tabs, of a pack blank are connected to one another and, if appropriate, to one or more separate blanks by the pack blank and/or the separate blank being provided in regions with individual, spatially separated portions of glue, in particular drops of glue, by means of a glue valve or a group of glue valves and the blank regions which are to be adhesively bonded together subsequently being held or pressed on one another. The invention furthermore relates to an apparatus for carrying out the method and to a valve which can be used preferably within the context of the method and as part of the apparatus. The valve here has a valve housing, an outlet or valve opening and a closure element with which the valve can be moved to and fro between an open position and a closed position.
2. Prior Art
During the production of cigarette packs, individual regions of the respective blank are adhesively bonded to one another. In addition, separate blanks, for example a collar or an internal blank in which the cigarette block is wrapped are generally glued to the blank. For this purpose, it is known to provide individual regions of the blank with individual portions of glue, in particular spots of glue, using glue valves.
However, during the adhesive bonding together of the blank regions, contamination of the glue frequently occurs. This is primarily because the glue valves apply too much glue in small regions of the blank. When the regions which are to be adhesively bonded together are pressed onto one another, the excess glue undesirably passes to the outside and contaminates other regions of the blank.
Furthermore, it is disadvantageous in the known gluing of cigarette pack blanks that the constant size or quantity of the glue portion which is set at the glue valves and is produced during a valve opening cycle changes inadvertently over the course of the production process. This is because the glue is inadvertently heated over the course of the production process by the waste heat of the packaging machine. This results in a reduction in the glue viscosity. At the beginning of production when all of the machine parts are still cold, the glue therefore has a greater viscosity than after a certain period of production. However, an inadvertently greater portion of glue quantity of the glue emerging from the valve during an individual opening cycle follows from a lower glue viscosity when the valve settings are otherwise unchanged.